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07/27/2021 05:55AM  
Is it me or am I imaging things. For the last several years, like 10-12 years, i have observed that there seems to be an increased trend in high base tstorms.

I travel all-over the country and this observation seems to more or less nationwide.

Have there been any similar observations from the professional weather people.

If so what is the current theory as to why.

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07/28/2021 04:19PM  
This is very good question. Something I have noticed too also over the past several years but not something that I directly thought about. I have given this some thought and ran it by some in the field. Likely is many factors, but here is one that maybe a reason among many;

It's obviously known that the earth's (surface) has warmed over the past- especially in the last 30-50 years. (mostly at the poles and mostly in the winter). Primarily- most of this warming has been caused by warming oceanic temps- esp the Pacific (oceans contain 99% of the heat capacity of the planet) -- so warming them has caused a natural release/ rise in water vapor which in turn has not allowed the earth to cool as much at night as when the oceans were cooler. When one looks at mixing ratio chart of water vapor- it's easier seen that increase in water vapor is huge in the warming of the earth.

Now at the onset this makes little sense. High base thunderstorms have high bases because of dry air (not moist) between them and the ground. However, high base thunderstorms also have rather "low tops" or anvils compared to more common "low base" storms.

It's commonly proven in the field that higher ranges (stratosphere,mesosphere) of the atmosphere are cooling,and cooling rater dramatically. Recently since 2016, observations have shown a "leaking" of this cooling into the troposphere (where our weather occurs). This cooling would also dry out the troposphere slightly and reduce tops of some thunderstorms because the condensation of some anvil tops would be happening lower in cooler air. "IF" this drying of the troposphere gets mixed around to lower levels you would experience more of what you are seeing. IN a nut- increase of high base thunderstorms "MAY" be a sign that the troposphere is cooling and drying on micro level, but able to be seen in high base storms.
Great question!!!
07/28/2021 07:40PM  

So to follow up if you don't mind.

I'll try and get this straight. I have read that solar cycles play an important roll in the temperature of our upper atmospheres. Our sun is coming out of a rather deep solar minimum. During a solar minimum as you know the sun spot count is almost zero and a reduction of solar radiation takes place. However during this time cosmic radiation increases, cooling our atmospheric temperatures by increasing clouds in the troposphere. I forget how/why this happens. I guess when you cool something it condenses and causes water vapor, (clouds). But how/why cosmic radiation does this ???i have no idea???

The opposite happens when the Sun is at its solar maximum. Increasing sun spots increase the amount of solar radiation we experience here on earth warming our atmosphere. Cosmic radiation decreases reducing clouds in the troposphere increasing our temp.

So I guess my follow up question would be, is the dramatic cooling that is being observed in the upper atmosphere a result of the Sun and its 11 year solar cycles.

It would be cool to read any studies on the high base tstorms.

I have also noticed the low anvils on some storms.

Thanks for the info.
07/28/2021 08:51PM  
So another question would be is there a known correlation between high base tstorms and the solar cycles. Thx.
07/28/2021 11:06PM  
The first thing that gets blamed is CO2 emissions for cooling of the upper atmosphere, (likely for funding) however almost all atmospheric scientists see the low solar as the reason.
You brought up some excellent points that are covered in this article that covers you first two questions.

As far studies showing a correlation between high bast tstorms and the solar cycles, I will look , but I doubt it. It's very difficult in obtaining funding that doesn't have anything to do with CO2 etc in climate studies. Not being political. Just stating a fact.

A little off topic , but as long as we are talking studies and something that really should see some $$ spent on is the MJO (Madden-Jullian Oscillation) found in the Indian and South Pacific. Over the last 5 years or so I have really delved into this MJO teleconnection and learned quite a bit and how very important it is for long range weather forecasts and hurricane development on this side of the world. In a future post - I will get into it. But in laymens terms it's measurement of the amount of water vapor/ and energy put into the atmosphere by thunderstorms ( or lack off) in the deep tropics in the Indian and Pacific oceans. It's amazing how much this drives the weather in the Eastern Half of the lower 48 and even the entire world. People talk of El NINO or LA NINA etc, but if these teleconnections across the globe were akin to football players on the field in order of who drives the game-- EL NINO / LA NINA is akin to a pro bowl Center while the MJO is Tom Brady. It's really is an amazing feature and I hope to show how it can be used to predict frequency of hurricanes and winter weather upcoming here later this year in future posts.
Thanks for reading.
07/29/2021 08:05PM  
Good article lots of stuff there.
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